Advances in the IoT and Smart Cities

1. Introduction

The proliferation of the Internet of Things (IoT) and the rise of smart cities are revolutionizing how societies operate and urban ecosystems are managed. This Special Issue of Applied Sciences, “Advances in the IoT and Smart Cities”, brings together contributions that explore the dynamic intersection of data-rich technologies, real-world applications, and emerging challenges in urban environments. IoT technologies are at the heart of smart city development, enabling automated and real-time decision-making for infrastructure, energy, mobility, and governance. However, as cities strive toward intelligence and sustainability, they encounter critical issues related to interoperability, privacy, performance, and system integration.

The aim of this Special Issue is to offer insights into the recent scientific and technological advances supporting the next generation of smart and connected urban infrastructures. These contributions demonstrate how innovations in data management, edge computing, behavior-driven development, and secure communication protocols are shaping the future of IoT in smart city applications. More importantly, the topics addressed resonate with global efforts to foster open smart city platforms and adopt frameworks that support data sovereignty and platform interoperability.

2. Overview of Contributions

This Special Issue features high-quality papers that advance our understanding and application of IoT technologies within smart city environments. In this collection, the integration of the digital Building Information Modelling (BIM) process and IoT in the construction industry is investigated, thus revealing a promising synergy between data-rich digital models and real-time sensor networks. Through a systematic literature review, the authors highlight the potential of BIM–IoT integration in improving construction safety, risk management, and sustainability, but also note that practical implementation remains limited due to technological and organizational constraints (contribution 1).

Moreover, an innovative real-time data processing framework for pavement quality monitoring using IoT and NoSQL technologies is also presented in this Special Issue. The system architecture presented supports rapid data ingestion and analytics at scale, with the experimental results demonstrating a 52-fold improvement in data processing speed over traditional systems. The research in this Special Issue shows how infrastructure monitoring in smart cities can benefit from optimized cloud-based data architectures (contribution 2).

In addition, other researchers address the complexity of modelling concurrent behaviors in IoT systems through enhancing the Gherkin language for behavior-driven development (BDD). A tool called concurrentSpec is proposed, which enables the accurate specification and execution of concurrent behaviors typical in distributed IoT environments. Their work fills a methodological gap, facilitating better alignment between IoT software specifications and real-world execution (contribution 3).

Furthermore, the privacy implications of personal and pseudo-anonymized data collection in smart cities are explored. Based on a research review, the authors identify the risks of de-anonymization and side-channel attacks while also surveying current anonymization techniques. The research presented in this Special Issue emphasizes that privacy-preserving architectures are critical in building citizen trust and enabling responsible data reuse in smart urban platforms (contribution 4).

Finally, a practical contribution to IoT interoperability in the form of a narrowband IoT (NB-IoT) relay for integrating IPv6-based 6LoWPAN sensor networks into legacy IPv4 infrastructures is presented. The approach leverages protocol translation and cloud integration through Home Assistant to simplify data exchange and increase platform compatibility. The work presented in this Special Issue directly responds to challenges of protocol diversity in IoT networks and exemplifies a lightweight solution for seamless integration (contribution 5).

3. Conclusions

The papers featured in this Special Issue demonstrate how recent advances in the Internet of Things are shaping the development of smarter and more resilient urban environments. The papers presented here address different topics, including common challenges and issues. Firstly, this Special Issues emphasizes the challenge of interoperability, both in terms of protocols and platforms, which continues to be a focal point for research. Secondly, it stresses how the efficient handling and analysis of real-time data streams are critical for enabling responsive and adaptive urban systems. Thirdly, it focuses on the development of robust methodologies for software development and validation, such as integrating behavior-driven development for concurrent behaviors, which ensures that smart systems behave as intended in complex, distributed environments. Finally, privacy and ethical data handling are vital components of responsible smart city governance.

Collectively, these contributions underline the importance of adopting open, secure, and scalable platforms that support the integration of diverse IoT technologies. The research presented in this Special Issue is aligned with broader efforts to adopt smart city platforms and transition toward interoperable architectures with IoT ecosystems, which is a prerequisite for long-term scalability and innovation in smart cities.